NEW YORK (AP) -- Doctors lined up at a public hearing to speak in favor of a proposed ban on large sugary drinks in New York, saying sodas and other sweetened beverages are a leading factor in the nation's fat problem. Critics see the plan as an assault on personal freedom.

New York City's health board was hearing testimony Tuesday on a proposal to combat a deadly obesity epidemic by banning restaurants, movie theaters and other eateries from serving giant-sized sugary drinks.

The panel is considering a rule that would limit soft-drink cup and bottle sizes at food service establishments to no larger than 16 ounces.

One doctor said before the hearing that the calorie-packed beverages consumers now down with abandon increase the risk of diabetes, and are responsible for a big share of the "massive suffering and premature death" linked to obesity.

"Soda in large amounts is metabolically toxic," said Walter Willett, a professor of epidemiology and nutrition at Harvard School of Public Health. "It's obvious that this is the right thing to do."

City Councilman Daniel Halloran III called the proposal a "feel-good placebo" that would hurt profit margins at small businesses, while failing to improve anyone's health.

He questioned whether a limit on the size of steak was around the corner.

Another critical councilman, Oliver Koppell, called the ban "a clear overreaching of government into people's everyday lives."

"This infringement on the rights of New Yorkers leads us to ask what will be banned next?"

The proposal requires only the approval of the Board of Health -- appointed by Mayor Michael Bloomberg -- to take effect. But opponents could still sue to block the ban, or they could convince legislators to step in and block the proposal.

The board is scheduled to vote on the measure Sept. 13.

Since Bloomberg proposed the ban in May, opponents including members of the restaurant and soft drink industries as well as libertarians have accused him of attempting to institute a "nanny state" with far-reaching government controls that infringe on individual choice. City officials, meanwhile, argue they are trying to save lives in the face of an epidemic that is killing New Yorkers and costing $4 billion a year.

The portion size restrictions would only apply to food-service businesses regulated by the Health Department, including restaurants, food carts, sports arenas and movie theaters. Grocery stores, drug stores and some convenience stores are regulated by the state and would be unaffected.

Drinks that are more than half milk or 70 percent juice would be exempt, and it wouldn't apply to lower-calorie drinks like water or diet soda, or to alcoholic beverages.

In a letter released Monday by The New England Journal of Medicine, New York University researchers said the ban could affect nearly two-thirds of drinks bought at the city's fast-food restaurants, according to a survey of more than 1,600 receipts. On average, sugary-drink buyers could consume 74 calories less per fast-food outing, the letter said.

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